Seventy patients who undergo STSG procedure in Kaohsiung Veterans General Hospital will be recruited. Two donor sites of equal lengths and widths on the same thigh, which are at least 2 cm apart will be covered randomly with AA and BCT each. Wound healing rate and infection rate will be assessed at 7 and 14 days after surgery. Degrees of pain and itchiness will be assessed daily with Visual Analogue Scale for the first 7 post-operative days. Scar appearance will be assessed with Vancouver Scar Scale 1, 3 and 6 months post-operatively.